Additions: PIERIDAE. By J. Rober. 1015 



Certainly the imago does not leave the nest, when its wings are still soft. It is only the insect being ready 

 to fly that goes out of the bag. The oblong, peculiarly narrow shape and the somewhat proximally indented costal 

 margin of the forewing enable the imago to appress the wings lengthwise close to the body and in this way 

 to pass even narrow openings. Nevertheless a great number of imagines cannot get out of the comparatively 

 narrow holes of the extremely tenacious nests. But now we must consider tliat, at the beginning of the flying- 

 time of the Eucheira in the month of May, the rainy period sets in with heavy showers, so that the larval web 

 is turned by the water into a most flexible and ductile state, and the imago is in this way able to leave 

 its prison. That this theory is correct is manifested in a great number of the bags by the outlets of the 

 nests having been enlarged from inside, which was only possible by way of dampness. From bags not having 

 been moistened only single imagines will be able to get out, and in this case the eggs are deposited in the nest 

 and only the small laivae pass out into the open air, as has likewise been observed. The whole structure 

 of the wings shows that the imago is but a very incomplete and lazy flier. 



Of great interest were also the I'Xiierinients ■\\ith imagines having been l)red to test tiu-ir flying-power. 

 Tlie insects, on having been set free in the garden, exliibited a wearisome, unsteady and tottering flight of 

 short duration and had evidently great pains to reach by and l)y the height of the garden-wall near by (R. 

 Muller). 



In May 1911 P. Benard, on the Carboncillo Mine near Zacualjaan in tlie State of Mexico, made the 

 surprising discovery that Eucheira socialis regularly came to the electric arc-lamps of the mine at night (bet- 

 ween 8 antl 10 p. m.). We must remark thereby, that these lamps were in the immediate neighbourhood of 

 extensive stocks of Madrono which always bear a great lot of bags of Eucheira. Benard himself never observed 

 lepidoptera in this district in daj'time, as at any rate these specimens taken by him at night are the first flying 

 Eucheira observed in nature, of which the entomologists and collectors known to me here are aware of. 

 In my entomological practice I have often been able to observe RhoiDalocera on electric arc-lamps at night, 

 which is here in Mexico especially the case with Hesperiids, but they were always only single insects having 

 been scared up, which appears to be out of the question with the Eucheira. At any rate this nocturnal flight 

 explains the remarkable absence of the insect in daytime, and we find in this most interesting diiunal lepi- 

 dopteron the fact being quite unique for a Pierid, that both the larva and imago exliibit entirely the habits 

 of a nocturnal lepidoptcion, so that we must regard this insect to number among the most inteiesting features 

 of the copious and multiform lepidopteral fauna of Mexico and even of the whole world. That the local (Mexican) 

 collectors have not noticed this nocturnal flight before, may be chiefly due to the fact that the arc-lamps 

 were too far away from the woods and food-trees as to be reached by the Eucheira with their limited flying- 

 power, and that here in the Valle de Mexico, as in many other districts, the lepidoj^tera have disappeared in 

 the immediate neighbourhood of the settlements, since the pupae are eagerly collected by the native Indians 

 and eaten as a delicacy." (Carlos Hoffmann.) 



As the figure on t. IS a has been reproduced according to an old, faded specimen (fresh specimens 

 were not to be obtained at that time), we prochice the figure of a o fiom a fresh specimen. In the 

 structure of the veins of this species there occur extensive variations, in the subcostal and discoccllular veins, 

 which, however, are not confined to the single sexes, but are also found in one and the same sjjecimen. Carlos 

 Hoffmann also has ascertained an intense variability in the white marking, thus there occur J(^ with almost 

 black Iiindwings, whereas the 5 ^J^J ^i^^ 9 5$ exhibit but slight differences in this respect. 



T. macrodice Stgr. (18 c, d) is declared by Pedro Jorgen.sen who edited a monograjjhy on the Pierids 

 of Argentina and the neighbouring districts to be a separate species different from itiicrodice Blch. (p. 5()), but 

 owing to the lack of material the latter could not be figured. ■ — ■ macrodice also occurs in Argentina. 



T. orthodice Weym. (18 e). Of this species Pedro Jorgensen also figured the $. It has a broad black 

 margin of the forewing, into which the white border of the black sagittiform spots extends; the white veins 

 of the hindwings are above and beneath rather broadly bordered with black, in a similar way as in fyrrhomma 

 (18 d ; the forewing beneath exhibits no other marking but the fine black scaling of the veins. It also occurs 

 in Argentina (Salta, Caltamarca). 



T. deniodice Blch. has been found again by Pedro Jorgensen in South Patagonia and Fuegia. The 

 figured specimens (194 a) are from Patagonia (Chubut). 



T. sagiUata Rob. (18 e) has been declared by Pedro Jorgensen to be a distinct species. 



T. joergenseni sp. nov. (194 a) from Ecuador (Baurs) is before me in a (J. It resembles sagiUnta (IS e), jocnii'nsrn;. 

 but it has much fainter markings on the forewing above, and the hindwing is not marked except a fine black 

 marginal line and insignificant black scaling of the veins; the yellow lines feebly show through from beneath. 

 Tlie ]3alpi are below in sagittata yeUow and black, whilst in joergensoii they are only black-haired, the anteimae 



